Author Keywords: Vegetation; natural covering; green covering; field survey; urban area 相似文献
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1.
Tom Müller 《Biodiversity and Conservation》1994,3(2):116-125
The need to integratein situ conservation into the planning process is outlined, and the importance of vegetation survey to determine conservation priorities and to identify areas suitable forin situ conservation is stressed. A case is presented, drawing on experience gained in Zimbabwe, of how a botanical institute can become an integral part of biological conservation. The institute should consist of a herbarium, a botanical garden, a gene bank and a vegetation survey unit. The function of each section, how they interlink, and how they can be integrated are discussed. 相似文献
2.
3.
HAL WHITEHEAD 《The Journal of wildlife management》2009,73(6):1000-1009
ABSTRACT Conventional distance sampling, the most-used method of estimating animal density and abundance, requires ranges to detected individuals, which are not easily measured for vocalizations. However, in some circumstances the sequential pattern of detection of vocalizations along a transect line gives information about the range of detection. Thus, from a one-dimensional acoustic point-transect survey (i.e., records of vocalizations detected or not detected at regularly spaced listening stations) it is possible to obtain a useful estimate of density or abundance. I developed equations for estimation of density for one-dimensional surveys. Using simulations I found that for the method to have little bias when both range of detection and rate of vocalization need to be estimated, stations needed to be spaced at 30–80% of the range of detection and the rate of vocalization should be >0.7. If either the range of detection or rate of vocalization is known, conditions are relaxed, and when both parameters are known the method works well almost universally. In favorable conditions for one-dimensional methods, estimated abundances have overall errors not much larger than those from conventional line-transect distance sampling. The methods appeared useful when applied to real acoustic data from whale surveys. The techniques may also be useful in surveys with nonacoustic detection of animals. 相似文献
4.
Not only Swedish studies, but also several international studies, claim an increase in anti-Semitic attitudes in recent decades. As prejudice is acquired in the early years of socialization, and/or is innate and fairly stable over the life cycle, examining adolescents’ attitudes is vitally important. Hence, by controlling for individual demographic and socio-economic background factors, we study two interrelated questions: Has anti-Semitism among Swedish secondary school-age youths changed between 2003 and 2009? Are changes equal across groups, with a specific focus on religious groups? Using two unique cross-section surveys of secondary school-age students in Sweden for the years 2003 and 2009, we try to address the above questions. Our analysis shows, in contrast to the views of the general public and other related studies, that anti-Semitism has decreased slightly during the examined period. Moreover, the study finds a variation in anti-Semitism by religious affiliation: it has increased among Muslim youth, but remains stable in other groups. 相似文献
5.
Andrew B. Stein Todd K. Fuller Laurie L. Marker 《Biodiversity and Conservation》2008,17(14):3579-3587
In northcentral Namibia, Waterberg Plateau Park (WPP) is a protected area that acts as a refuge for rare and endangered species,
while the farmlands surrounding the Park are managed for livestock production, but support populations of wildlife for game
farming, trophy hunting, and conservation. During June–October 2006, camera-traps were set within and surrounding WPP to assess
leopard (Panthera pardus) density (n = 19 camera stations and 946 camera-trap-nights). Fortuitously, photographic results (2,265 photos of identifiable mammal
(n = 37) and bird (n = 25) species) allowed us to assess aspects of species diversity and differences among the Park, the farmland areas along
the Waterberg Plateau escarpment, and the flatlands surrounding the escarpment. Species composition among the three areas
was markedly different, and made sense with respect to differences in habitat and management features. Camera-trapping efforts,
although intended for a narrow purpose, may also provide a rather robust record of differences in mammal and bird diversity
in adjacent habitats and can be incorporated into long-term monitoring programs. 相似文献
6.
扁桃体切除术是耳鼻咽喉科最常见的手术之一,临床上治疗由于扁桃体肥大所致的儿童睡眠阻塞性呼吸暂停综合征,最常用的手术方式为双侧扁桃体切除术。扁桃体在儿童生长发育过程中具有重要的免疫功能,完全切除扁桃体对儿童的免疫功能具有一定的影响。且扁桃体全部切除术后常见一些并发症如出血及疼痛,这使得许多学者提出了扁桃体部分切除术。扁桃体部分切除术较扁桃体全部切除术相比,手术时间短、术后并发症少,在缓解儿童阻塞症状的同时,保留了一部分扁桃体,对于免疫功能也有一定的保留。本文将从扁桃体部分切除术治疗儿童睡眠呼吸暂停综合征的临床疗效以及术后出血、术后疼痛方面作一综述,为扁桃体部分切除术应用于临床提供合理依据。 相似文献
7.
Tadahisa Katayama Akio Ishii Tetsuo Hayashi Jun-ichiro Tsutsumi 《Journal of thermal biology》1993,18(5-6):571-576
1. 1. Three kinds of field survey on different scales were carried out in Fukuoka City in summer to examine the relationship between the quantity of vegetation and air temperature.
2. 2. The field of the largerst scale measurement is across the city.
3. 3. Several parks and shrines of various sizes in the city were selected as other measurement areas.
4. 4. The most detailed measurements are carried out in a park with an area of 1.25 ha located in a down town area of the city.
5. 5. Though the amount of vegetation is expressed in a unique way in each survey, it is clearly found that the greener it is, the lower is the air temperature.
8.
D.J. BULLOCK 《Biological journal of the Linnean Society. Linnean Society of London》1995,56(S1):119-126
A preliminary analysis of the use by bats of National Trust properties revealed that all 14 resident species have been recorded. Comparison with a national database of records for Britain managed by English Nature (NCC Bat database) showed that the scarcer species are better represented roosting in buildings on Trust properties than in other buildings. In addition, survey of Trust properties has shown that a high proportion of buildings are used by bats. Bats provide unusual wildlife links between buildings, gardens and countryside through which the Trust can promote nature conservation, and resolve conflicts between building or landscape restoration and the bat habitat requirements. The role of the County Bat Groups in survey and promotion of bats on Trust properties is becoming increasingly important, especially if we are able to identify key properties for bats. 相似文献
9.
Systems ecological accounting for wastewater treatment engineering: Method,indicator and application
Wastewater treatment facility is vital for sustainable urban development. In the course of removing contaminants and discharging ready-for-reuse water, wastewater treatment consumes resources and triggers environmental emission during its lifetime. A comprehensive framework to analyze the embodied ecological elements as natural resources and environmental emissions of wastewater treatment is presented in this work. The systems method as a combination of process and input–output analyses is applied and a set of indicators are accordingly devised. Two representative ecological elements, i.e., greenhouse gases emissions and solar emergy of alternative wastewater treatment systems, i.e., a traditional activated sludge wastewater treatment plant and a constructed wetland have been taken into consideration. For each ecological element, five indicators have been calculated and compared to assess the impact on climate change and resources utilizing style of the case systems. The framework raised in this paper is fully supportive for optimal decision-making among different wastewater treatment technologies, and could be transplanted to be applied to systems ecological accounting for other production systems. 相似文献
10.
A total of 270 soil samples from 30 different habitats in 10 geographic regions of California were evaluated for the presence of rhabditid entomopathogenic nematodes. Nematodes were isolated from 26.3% of the samples. The recovered isolates were identified as Steinernema carpocapsae, S. feltiae, S. kraussei, S. longicaudum, S. oregonense, Heterorhabditis marelatus and H.bacteriophora. Among the steinernematids, S. kraussei and S. feltiae were the most commonly encountered species, generally occurring in acidic soils high in organic matter. Among the heterorhabditids, H. bacteriophora was isolated along the southern coast, whereas H. marelatus was recovered along the northern coast of California. Steinernematids were recovered from coniferous forests, oak woodlands and grasslands whereas heterorhabditids were isolated from coastal marshes. 相似文献